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PLANT RESEARCH STATION. The Plant Research Station is an activity of the Department which is conducted in co-operation with the Department of Agriculture. The work of the station includes sections which deal specifically with regular routine matters, and other sections which are engaged purely on research investigations. The work at the Plant Research Station proceeds in close association with that of the Wheat Research Institute, and the fruit research programme of the Department of Scientific and Industrial Research. The following report deals, in brief form, principally with those activities which receive financial assistance from the Department of Scientific and Industrial Research. Mr. A. H. Cockayne is the Director of the Plant Research Station. Botanical Section. (1) Identification of Specimens. —Some four thousand specimens of plants have been received by the Systematic Botanist for identification and advice. This is particularly essential where the specimens are those of lately imported plants which are likely to constitute a weed menace. During the year a large number of specimens of plants which have been suspected of being poisonous to live-stock have been received. The identification work carried out also serves very usefully where species figure as indicator plants of soil and habitat conditions. (2) Herbarium. —Numerous additions were made to all sections of the herbarium during the year, so that it now contains close on twenty thousand sheets. Special attention has been devoted to grasses and to mosses of agricultural importance. (3) Systematics. —The systematic investigation of the grasses and rushes of New Zealand have been carried a stage further, and additional work done on the whole alien flora of New Zealand, especially those possessing economic significance. Lucerne types established in New Zealand have also been receiving attention, and in this work co-operation is being effected with workers in other countries on a project entitled, " International Test of Types of Lucerne." (4) jFruit-trees.—ln association with the fruit research scheme, work dealing with root-stocks, propagation of fruit-trees, and strain differences is proceeding, and the progress in this connection is reported in the section dealing with fruit research. Chemical Section. (1) Pasture Analysis. —The Chemist has been engaged on the analysis of pasture and soil samples from the Marton mowing trials, determinations being made of the effect of fertilizers, grazing, and season upon the chemical composition of pastures from this area. (2) Manurial Investigations. —The effect of applications of lime on the movement of phosphate or superphosphate, basic slag, and North African phosphates in the soil conditions of Marton are being continued. (3) Rape Analysis. —An investigation of the chemical composition of the various types of rape was carried out in co-operation with the Agronomy Section, with the object of correlating chemical data with that received from feeding trials. This analytical work is associated with that which has already been done in connection with the different strains of rape which are being used for lambfattening purposes in the arable portions of the Dominion. (4) White Clover. —With the object of determining type of white clover, using hydrocyanic acid content as a basis, analyses of the different strains established at the Station have been continued. The correlation between the HCN content and type has been well maintained, but, in general, the figures for the HCN content have been considerably lower during the present year. FIELD EXPERIMENTAL SECTION. (1) Strain Tests with Perennial Rye-grass from the Hawke's Bay and Canterbury Districts. —These trials, conducted in the Canterbury District over a period of four years, have been maintained. Those areas sown with certified perennial Hawke's Bay rye-grass have, up to the present time, given an average increase of up to 30 per cent, more grazing than those sown with the Canterbury strain of rye-grass, the margin of superiority being fairly constant during the past three seasons. In the area sown with Hawke's Bay rye-grass, this grass is still dominant, whereas in the others cocksfoot and white clover have come in to such an extent as now to form the dominant constituents of the pastures. (2) Observational Top-dressing Trials. —Two hundred and fifty observational top-dressing trials, arranged for the purpose of surveying the response of New Zealand grasslands to lime, phosphate, and potash, have been continued. Prom these the most prominent feature of the year is the marked responses to potash within two months of its application, which have appeared in North Taranaki. The results have been so consistent as to warrant a recommendation being made to farmers in this district that they should include potash in their manurial mixtures. In some districts it has been found that no response has been shown to superphosphate, and while there are cases where this may be attributed to a deficiency of lime, there are others where neither super nor super plus lime have produced visible results.

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